Mustache Conditions and Loops

javascript, mustache, ruby-on-rails

Solution

There are two solutions to your problem.

Using selections and inverted selections

Here is an example from the mustache documentation:

{
  "repos": []
}

Template:

{{#repos}}<b>{{name}}</b>{{/repos}}
{{^repos}}No repos :({{/repos}}

Output:

No repos :(

As you see the inverted selections let me do conditional logic. In your case it would look something like:

Json:

var viewModel = {
    badges:[]//badges here
}
viewModel.anyBadges = badges.length >0;

Mustache:

    <div class="badges-unlocked">
   {{#anyBadges}}
      <h2>Unlocked!</h2>
   {{/anyBadges}}
   {{#badges_unlocked}}
      <a href="#" class="badge">
        <strong>{{ name }}</strong>
      </a>
   {{/badges_unlocked}}

Don't do logic in logic-less templating

This is what I would do. If you have conditional logic in your Mustache templates I think you're doing it wrong. You can either use Handlebars instead which is much more advanced in this regard or move your logic someplace else (to your javascript).

Please see the Mustache readme

Problem

Here are the resources: JSON ``` { "badges":{ "unlocked": [ {"name": "Win 1"}, {"name": "Win 2"}, {"name": "Win 3"} ], "locked":[ {"name": "Lose 1"}, {"name": "Lose 2"}, {"name": "Lose 3"} ] } } ``` Algorithm ``` {{ if_has_badges }} <div class="badges"> <h1>Badges</h1> {{ if_has_badges_unlocked }} <div class="badges-unlocked"> <h2>Unlocked!</h2> {{ loop_badges_unlocked }} <a href="#" class="badge"> <strong>{{ name }}</strong> </a> {{ end_loop_badges_unlocked }} </div> {{ end_if_has_badges_unlocked }} {{ if_has_badges_locked }} <div class="badges-locked"> <h2>Locked!</h2> {{ loop_badges_locked }} <a href="#" class="badge"> <strong>{{ name }}</strong> </a> {{ end_loop_badges_locked }} </div> {{ end_if_has_badges_locked }} </div> {{ end_if_has_badges }} ``` How I can write this algorithm to work with Mustache compiler? I need to do this to work with two sides, first is the RubyOnRails application and the second is the client-side (JavaScript).

Original source

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